pH/TDS/PPM levels for Hydroponic plants

The
pH scale is a way to measure the Acid or Basic (alkaline) in nutrient
solution. The official definition of pH is: a unit of measure that
describes the degree of acidity or alkalinity of a liquid solution. It
is measured on a scale of 0 to 14. Acids are in a range from 0 to 7,
with lower numbers being a stronger acid. Alkaline is in the range from
7 to 14, with the higher numbers being a stronger base.

The
pH of the nutrient solution is essential to the plants hearth because
it will affect how well each element can pass through the root cell
wall and nourish the plant. When the pH of the nutrient solution is out
of balance the plants are not able uptake the nutrients in the water,
basically starving them, even when there is plenty of food.

The
pH requirements for plants are not the same for all plants and you
should not grow plants with different pH requirements in the same
nutrient solution. You will wind up feeding one plant and starving the
other, no mater what pH level you keep it at.

We have listed some plant requirements and categorized them by Fruit, Vegetables, Herbs and Flowers
for your convenience. Exact plant requirements can very depending on
many variables, so it is much more important to be in the ballpark
rather than on the decimal point in regards to pH.

Measuring
and adjusting the pH of your nutrient solution is quite simple to do,
but should be done daily to insure a constant pH level. Testing can be
done inexpensively (under $10) using a pH testing kit that generally
consist of a small vial that you put some of the solution in. Then you
just add some drops to it and shake it up and compare the resulting
color to a color chart to get the results. Also you can use pH testing
strips. They work basically the same but it's a small strip of paper
you dip in the nutrient solution then compare to the color chart.

If
you are looking to be more accurate you can use a pH testing meter.
They are electronic and measures down to the decimal point. These pH
testing meters can vary in price but are usually under $100.

When
measuring the pH you want to mix your nutrients with the water
completely first to ensure a true reading. If the reading is not at the
proper level you need to adjust it using pH adjusters called "pH up"
and "pH down," Depending on weather your reading is to high or to low.
If it's too high use the pH down, and if it's too low use the pH up.
The pH adjusters can come in a dry or liquid form, either will work
fine but make sure you mix it completely before taking another reading.
The adjusters vary in price depending on manufacture but are not that
expensive